Parker and Lampard were colleagues for club and country, while they have also spent time together on holiday.
But Blues manager Lampard admits that sometimes it can be more satisfying to beat a friend than an enemy.
He said: “I definitely saw fight in Scott when he was here at Chelsea and I guess he would have wanted to play more.
“He left to play, which is always a great sign. He went to play more and his career was fantastic wherever he went after that, and his England career.
“That's a sign of the man he is and the professional he was. I also find Scott very genuine, a straight-talker, and very hard working.
“We have holidayed in the same destination a couple of times and had lunches together, and a few drinks here and there, so we are certainly close – as much as that goes.
“You can have friends in football – I have – but when you're very driven, your job takes you in different directions, particularly when you're a manager.
“It's very hard to have too much small talk and I'm guessing some of my friends, and possibly family, will agree with this given how rubbish I am at texting people back and stuff, because
I am consumed with this job.
“But with Scott, I appreciate he's got a lot on his hands, as I have, and I let him get on with that.
“And the other thing with friends is when you're driven in this game, you want to beat your friends, sometimes maybe even more than you want to beat your enemies.
“But it doesn't change anything in terms of how you approach the game.
“I'm sure Scott won't mind me saying that and he'll feel the same. At the end of the day, it's points for our teams that we both need at this moment."